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Air Pressure

  • Created: Tue, 17 Jun 2014

Optimal tire performance requires correct inflation. Tire pressure can change over time due to climate changes, natural air loss, or other factors. To maintain proper inflation, you should check your tires periodically. Under inflation of tires can lead to early or uneven wear, traction problems, and stability problems.

  • Maintaining correct tire inflation pressure helps optimize tire performance and fuel economy. Correct tire inflation pressure allows drivers to experience tire comfort, durability and performance designed to match the needs of their vehicles. Tire deflection (the tread and sidewall flexing where the tread comes into contact with the road) will remain as originally designed and excessive sidewall flexing and tread squirm will be avoided. Heat buildup will be managed and rolling resistance will be appropriate. Proper tire inflation pressure also stabilizes the tire's structure, blending the tire's responsiveness, traction and handling.
    Can you easily identify which tire is 30% underinflated? Here is what they would look like in the morning parked in your garage.
    (Roll your mouse across the pictures to find out if you were right.)
  • An underinflated tire can't maintain its shape and becomes flatter than intended while in contact with the road. If a vehicle’s tires are underinflated by only 6 psi it could lead to tire failure. Additionally, the tire’s tread life could be reduced by as much as 25%. Lower inflation pressure will allow the tire to deflect (bend) more as it rolls. This will build up internal heat, increase rolling resistance and cause a reduction in fuel economy of up to 5%. You would experience a significant loss of steering precision and cornering stability. While 6 psi doesn’t seem excessively low, remember, it usually represents about 20% of the tire’s recommended pressure.
  • An overinflated tire is stiff and unyielding and the size of its footprint in contact with the road is reduced. If a vehicle's tires are overinflated by 6 psi, they could be damaged more easily when running over potholes or debris in the road. Higher inflated tires cannot isolate road irregularities well, causing them to ride harsher. However, higher inflation pressures usually provide an improvement in steering response and cornering stability up to a point. This is why participants who use street tires in autocrosses, track events and road races run higher than normal inflation pressures. The pressure must be checked with a quality air gauge as the inflation pressure cannot be accurately estimated through visual inspection.

To maintain more constant tire pressure, we recommend filling your tires with nitrogen because it is an inert gas with a very low freezing temperature so less expansion and contraction.

  • Cars - Most passenger cars run best with 40 pounds air pressure. Slightly higher pressure than the manufacturer's standard recommendations will give a slightly harsher ride but will increase the gas mileage and tire wear while protecting your wheels from pothole damage.
  • Trucks - They require higher pressure than car tires, but the rules of air pressure still apply. 
  • Nitrogen is a larger molecule than oxygen. This results in slower leakage from tires. Tires wear longer, run cooler and wheels are not subject to corrosion through oxidation and the effects of condensed water inside the tire. 

    Systems are now available to fill your tires with nitrogen and we strongly recommend its use.

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